


Guardian, meet Angel: A Good Omens/Invisible Library crossover

by slider501



Category: Good Omens - Neil Gaiman & Terry Pratchett, The Invisible Library - Genevieve Cogman
Genre: Aziraphale being overprotective of his books, Crossover, Crowley being overprotective of Aziraphale, Implied Aziraphale/Crowley, Pre-Canon: Good Omens, or I guess it could be post armageddon if you really want
Language: English
Status: Completed
Published: 2019-07-28
Updated: 2019-07-29
Packaged: 2020-07-23 19:42:36
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 4
Words: 3,859
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20013760
Author URL: https://archiveofourown.org/users/slider501/pseuds/slider501
Summary: The Invisible Library exists between alternate worlds, and its agents collect books from the different dimensions and bring them to the library for preservation. Today, Agent Morgan’s mission is to retrieve a book from a humble Soho shop owned by the eccentric A.Z. Fell.





	1. Chapter 1

According to the Library’s cosmological model, there are lawful and chaotic forces active in all worlds. Sometimes they take on a physical form, appearing as entities and personifications of law and order. Morgan flipped through the file of her latest assignment. Her destination, alternate B-617, seemed to be uniquely affected by chaos. Most chaos-inflicted alternates manifested in vampires, werewolves, or lesser Fae— and she’d had her fair share of run-ins with them in the past. This one, however, had Angels, Demons, Biblical Horsemen, and Hellhounds. Atlantis had even risen here once. She frowned and closed the file. She had never heard of an alternate with ecclesiastical-inspired entities but she supposed it wasn’t out of the bounds of probability. She corrected herself; in this world, the Christian mythos was inspired by the entities, not the other way around. 

Morgan sat in a London subway car and ran through the details of the mission in her mind. She was sent to secure an original Wilde book, a novel that existed in this alternate but never came to be in any others. The bookshop where she was headed boasted an extensive collection of Wilde first-editions. The train rumbled to a stop, and Morgan exited into the Totten Court Road station among a crowd of sleepy commuters. She smiled, and couldn’t help but start a jaunty walk to her destination. Bookshop retrievals were by far the most pain-free missions. If a book you needed was in a bookshop, you bought it. Simple as that. This made them wildly more convenient than missions involving theft, trickery, or other dishonest means of procurement. It also made them ideal for the agent who wanted to sneak in a bit of sightseeing. 

She walked down a Soho sidewalk and imagined taking a quick stroll through St. James Park once this was all finished. She spotted the bookshop down the road, bright red and emblazoned with _A.Z. Fell & Co._ in gold lettering. Despite her pleasant demeanor, Morgan felt a twinge of nervousness. She had come across some reviews of the shop that were… questionable, to say the least. 

_Run by a delightfully frumpy guy. Oddest opening hours I’ve ever seen, but neat collection of books. Left without buying anything because he said the shop had a mold problem and the book I wanted was infected with asbestos. 2 stars._

_Mr. Fell was very nice at first, but refused to sell me a book! It’s like he doesn’t want to sell any books (which are all grossly overpriced anyway). Pretty sure he wants a library and not a bookshop. Go elsewhere. 1 star._

_There was a massive snake in the shop!!! I’m not joking!!!!!!! Mr. Fell didn’t seem concerned at all WTF. 1 star._

Undeterred, Morgan entered the bookshop. A little bell jingled as she closed the door, summoning a man from the back room. He had light hair and wore a beige jacket over a brown vest and tartan bow tie. 

“Good morning,” he said, smiling politely. 

“You must be Mr. Fell,” Morgan said, smiling in return. “I hear you have an impressive collection of Oscar Wilde books. World renowned even.” Mr. Fell beamed at her.

“Why yes!” he said. He bolted into the rows of bookshelves, returning moments later with an armful of novels and pamphlets. He plunked his haul on an empty table and beckoned Morgan over with a wave of his hand. She sat in a plush green armchair and watched him gingerly take each book off the pile and place it on the table. As he rambled excitedly about his first edition copy of _The Selfless Giant_ , Morgan examined the bookshop’s interior. The shop was clearly well-loved— so full of love that she could feel it physically, even. It possessed the type of loveliness that made her want to sit in this comfy chair and curl up with a book for hours. Not a speck of dust in sight, not a book out of place. Oddly enough, there was no cash register to be seen.

“Ah! And this is a draft of Wilde’s poem _Ravenna_. I think I was there when he wrote that one.” Morgan’s attention snapped back to Mr. Fell. 

“You were there?” She said, furrowing her brow. Mr. Fell’s eyes widened and his cheeks blushed pink. 

“Er— Well no, of course not. Simply a slip of the tongue. I do apologize.” He nervously fiddled with his coat and looked away. Morgan squinted suspiciously at him, but didn’t push the issue further. 

“Do you have his book titled _Death Of Destiny?”_ She asked. Mr. Fell brightened immediately, once again enthusiastically picking through his pile and muttering about Wilde’s literary career as if the last awkward exchange never happened. He carefully extracted a small, hardcover book from the middle of his stack, taking great care to not tip the whole thing over. 

“This is the original version of _Death Of Destiny_ , written by hand before being sent off for typing. Some might still call it a draft for that reason, but I digress,” said Mr. Fell. 

“Can I see it?” Asked Morgan. Mr. Fell nodded, and she reached across the table and picked the book up. It was bound in pale purple cloth with a gilt lettered spine and gilt floral motifs on the covers. She delicately thumbed through the pages, studying the handwriting and inspecting the book for identifying features. She could feel Mr. Fell’s stare boring into her skull, as if she might destroy the precious item with a single erroneous breath. “It’s beautiful,” she said. Mr. Fell grinned in return.

“Yes, isn’t it? There’s something utterly magnificent about old books. Especially when they are bound by hand. Truly a lost art.”

“It would please me very much to buy this book,” said Morgan. “How much?” Mr. Fell’s expression lost all warmth. 

“Well, it’s a very rare item. Its price easily outmatches any decent person’s bank account. Sorry to disappoint you.” He frowned and stuck an arm out to take the book back from her. _Ah, so this is what the reviewers were referring to,_ she thought. 

She did not hand him the book.

“I assure you that money is no object. Name your price,” she said. 

“It’s not just an original. This copy was one of 5 printed on vellum and given to Wilde’s few loyal friends. It is surely too expensive for you,” said Mr. Fell, waved his hand dismissively. 

“I’ll decide that for myself, please,” said Morgan. Mr. Fell glared at her, which she returned with an innocent smile. “I don’t mean to offend.”

“I’m sorry, but I won’t be selling you this book today.” He said, in a tone plainly non-apologetic. He stood up and curtly gestured to the entrance. “In fact, the store is closing for the day.” Before Morgan could protest, Mr. Fell stepped around the table and plucked the book from her hands, sweeping her out the door like a pile of crumbs. On the store’s front steps, she exclaimed, 

“Mr. Fell I really think—“

“Sorry this didn’t work out. Have a pleasant morning.” He slammed the door in her face and turned the sign to _CLOSED._ Morgan sighed. Her watch read 10:16am. This mission was not going to be as simple as she hoped. 

**Notes for the Chapter:**

> GLOSSARY--
> 
> The Library: An all-seeing, inter-dimensional library whose mission is to collect and preserve books from all alternate universes.
> 
> The Language: The otherworldly language which Librarians use for their magic, can be used for warping reality to do whatever the speaker wants it to do, within limits. When heard by someone not bound to the Library, the spell sounds like the listener's native language. 
> 
> Runes: The tattoos a Librarian has on their spine that binds them to the Library and channels their magic use.


	2. Chapter 2

Morgan returned to the shop the following afternoon. When she entered, she found Mr. Fell tucked away at a desk in the corner, so absorbed in his book that he didn’t notice her arrival. She stood silently for a few moments, observing how he gracefully turned its pages and scratched symbols in an accompanying notebook. The bookshop was serene, glowing with afternoon sunshine, perfumed with the scent of Green Tea and well-loved literature, and silent save for the soft rustling of paper. 

“Good afternoon, Mr. Fell,” said Morgan. He shrieked and jumped in his seat, knocking a teacup over.

“My heavens! I didn’t hear you come in, dear girl.” Mr. Fell held a hand to his chest and exhaled, righting the teacup. Somehow, the contents of the spilled tea had disappeared and none of the paper was stained. “To what do I owe the pleasure of your company?” He said smiling warmly at her.

“Yesterday you said you wouldn’t sell me your book. I was hoping that today you’d reconsider,” she said.

“Oh,” he replied, scowling. He glanced down at his desk. When his eyes rose, his expression had morphed into a polite smile, but Morgan could tell something sinister lay just beneath it. “Well I suppose I have to think about it,” he said with a sweet inflection like he was _just barely_ tolerating her request. Morgan sniffed. The bookshop was now rank with an unpleasant stench, like stinky cabbage or moldy lake water. She felt a fierce prickling down the runes on her spine and her eyes widened. 

_Chaos magic._

“Like I said yesterday, I, um, I pretty sure I can— I’m certain I can afford to purchase it no matter the price,” she stuttered. _Shit. How did I not realize this sooner?_ She tried to keep talking and buy herself time to think. _Were the lights this painfully bright yesterday?_ “I’m financially backed by an organization—“

“Oh? Which organization?” Mr. Fell probed. He raised an eyebrow at her. “The Freemasons? The Order of Chaeronea?” 

“None of the above, I’m afraid.” 

“Hmph. Well, I don’t make deals with shady organizations, so unfortunately you’re out of luck. Don’t take it personally. Simply a matter of principle.” He shrugged as if to say _Well that’s that._ Morgan would have scoffed at his remark if she hadn’t still been stunned by her realization. She didn’t even know what she was dealing with. _A demon, probably._

She swallowed and said, “I promise you that the organization is perfectly reputable. Now please, Mr. Fell. Surely we can come to some agreement.” He shook his head. 

“No, I think this matter is spoken for. I believe it’s time for you to go. In fact, you will exit my shop and find yourself perfectly content and no longer interested in purchasing the book. And perhaps you will have a lovely walk to wherever you are returning to, thinking about happy things and humming your favorite song.” Her tattoo was burning now. She suspected that if he had directed his statement at anyone else, his words would be a command they were not at will to disobey, whereas to her they were simply a strong suggestion. Still, it didn’t seem wise to stick around. 

“Why, I agree. Have a great day, Mr. Fell,” Morgan said, starting for the door. 

“And you as well, my dear,” he responded with a cordial wave. She stepped out into the street and let the door swing shut behind her. She rubbed her eyes and groaned. _A demon. Wonderful._ She wasn’t sure what confused her more: That a demon had decided to spend his eternal life hoarding books, or that the Library hadn’t known about it. She had hoped they would have mentioned something like _By the way, the shop is owned by a creature of Chaos whose power we don’t know the limits of and who unreservedly uses it to scare away potential customers._ Such sloppiness with their intel was extremely rare and greatly concerning. She sighed and began her walk back to her lodgings. Maybe it was just the shop-owner’s spell interfering with her mood, but it was indeed a pleasant afternoon. She resisted the urge to hum her favorite song.

**Notes for the Chapter:**

> GLOSSARY--
> 
> The Library: An all-seeing, inter-dimensional library whose mission is to collect and preserve books from all alternate universes.
> 
> The Language: The otherworldly language which Librarians use for their magic, can be used for warping reality to do whatever the speaker wants it to do, within limits. When heard by someone not bound to the Library, the spell sounds like the listener's native language. 
> 
> Runes: The tattoos a Librarian has on their spine that binds them to the Library and channels their magic use.


	3. Chapter 3

The next morning, Morgan began her watch on the bookshop from a small cafe down the block. Sitting by a window with a cup of coffee and a book for light reading, she spied on the shop for hours. She watched the occasional curious passerby duck in and out (none of them left with a book), but overall the establishment was left alone. Morning turned to afternoon, and afternoon began to encroach on evening. Morgan was on her second croissant when a black Bentley pulled up to the shop’s front. It was a vintage car in excellent condition, but strikingly melodramatic against the quaint London backdrop. She stared, tapping her fingers on her cup in anticipation. The bookshop door opened and Mr. Fell walked outside. He waved excitedly at the car’s driver before locking the door behind him and climbing into the Bentley’s passenger seat. They lingered for a few moments before the car jolted to life, speeding away in a manner that was sure to attract police attention. Morgan sprang up and raced out of the cafe. She reached the front steps and after glancing around for suspicious bystanders, Morgan turned to the door. She leaned over and murmured in the Language, **“Lock on the bookshop door, open.”** The bolts clicked into place. She put a hand on the knob and braced herself for traps, but felt none. She slowly pushed the door open and crept into the bookshop. She could perceive that the lock had been charmed to be impervious to lock picking, and the windows charmed to be unbreakable. However, there were no wards or protections to fend off intruders like her. The shop didn’t have a human security system either.

The bookshop was just as it had been yesterday. Evening light streamed through the windows and cast the room in a pale glimmer. Morgan began poking around the shelves, scanning the books’ spines for recognizable titles. She found herself by a collection of Charles Dickens first editions, which were next to an assortment of novels by Fyodor Dostoyevsky. Those neighbored a few copies of Giovanni Boccacci's _Il Decameron_ , and beyond them a bundle of pamphlets written in what looked like the Phoenician alphabet. She shrugged and shook her head. Mr. Fell didn’t arrange his books by the alphabet or the Dewey Decimal system, or any other human system seen across the multiverse. Morgan was certain that there was a system, since there was no way a devoted shopkeep like himself _wouldn’t_ have one, but she had no clue what it was. 

While she inspected a shelf in the back, she heard the door swing open. Frozen in fear for only a moment, instinct took over and she darted into the backroom. She crouched behind a tall cabinet, trying to slow her panicked breathing. Pressed as close to the wall as she could manage, she heard the muffled voices of Mr. Fell and another man she didn’t recognize. 

“Is this really necessary, angel?” said the stranger. 

“Oh hush,” responded Mr. Fell.“I simply misplaced it and once it’s found we can head to dinner-” The man aggressively shushed Mr. Fell. 

“I think there’s someone in here,” he whispered. _Shit._

“What?” said Mr. Fell, fear creeping into his voice.

“I can smell them,” said the man. Morgan swore internally and weighed her options. There was no way she could overpower a demon, especially two of them. Fleeing wasn’t an option until she found the book. With a plan beginning to form, she rose from her crouched position, mustered up a facade that resembled calmness, and walked into the front room with her hands up diplomatically. 

Both men spun to face her.

“My goodness! _You_ again?” Shrieked Mr. Fell. His companion was a lanky man dressed in slim black clothing and round sunglasses. The man in black looked at him puzzled. 

“You know her?” he said, cocking an eyebrow. 

“She was here trying to purchase a book, but I sent her _away_.” Mr. Fell drew out the last word as if to say “ _and she wasn’t supposed to come back.”_

“Mr. Fell and I have met twice to discuss a purchase,” Morgan interrupted. She tried to look calm even though she was quaking inside. “We weren’t quite able to reach a deal, much to my disappointment.” 

“And now you were going to, what, plunder my shop?” spat Mr. Fell.

“Let me deal with her, angel,” said the man in black, taking a step forward. “Stealing is a sin after all,” he hissed. He smirked and stuck a forked tongue at her. 

“Oh, so you’re a demon too, then?” She stammered, trying to distract him. “Your magic won’t work on me. Not his either.” She gestured at Mr. Fell. The man froze startled. 

“How do you know about that?” He said.

“You- you think I’m a demon?” said Mr. Fell with immeasurable hurt in his voice. The man swiveled to look at Mr. Fell. His face had scrunched up and he seemed to be on the verge of tears. Silence hung awkwardly in the air. The man spun back to Morgan with a new rage in his eyes.

“ _APOLOGIZE!_ ” The man was seething like he embodied Lucifer himself. Morgan blinked in confusion. 

“What?” 

“You heard me!” The man barked, waving his arms aggressively. “He is Aziraphale and he is a principality of Her ethereal plane. Apologize to him!”

“Really, Crowley, it’s okay,” said Mr. Fell— Aziraphale— softly. 

“No, it’s not,” the other man— Crowley— said. He turned and glared at Morgan expectantly. Morgan decided that she could not afford to let the situation escalate further, lest she wound up on the receiving end of a hellish thrashing.

“I’m sorry,” she said. “I didn’t mean any offense.”

“I guess I _was_ rather rude to you…” Aziraphale replied, looking down sheepishly and wringing his hands.

“Enough,” interrupted Crowley. “The real question is, what the hell are you _?_ ” he growled, pointing rudely at her. _A human who works for a magic library and could be killed by a snap of your fingers._

“I can’t say.” She responded. 

“Can’t or won’t?” He snarled. 

“Won’t. Just know that I am a being of immense power, and you would not be wise to attack me.” Morgan hoped that sounded convincing. Crowley hesitated, clearly unsure if she was telling the truth. 

“Are you one of those girls from the Sisterhood of Myrios?” questioned Aziraphale. “They’re an all-female crime syndicate who think they’re demi-gods,” he clarified to Crowley. He turned back to her and said sternly, “If you leave now, I won’t report you to the local police.” 

Crowley scoffed, “You want to let her walk off?”

“Well, I don’t see any point in hurting her.”

“I ought to smite her off the bloody planet! Zira, she tried to steal your books!” Morgan winced at the thought of being smote. _Time to ramp up the act_. She invoked the Language, projecting loud enough for the whole shop to hear, “ **Books, rise off your shelves and shake.”** Crowley and Aziraphale gasped as the books did exactly that, every book in eyesight raising 6 inches off its perch and trembling in the air before dropping back to its previous position. Due to the nature of the Language, Morgan knew they must have heard her words in their native celestial tongue.

“How- how do you know that?” stuttered Crowley, whose face had gone pale. Aziraphale was speechless. She prayed that her small action hadn’t damaged any of his books or else he surely would unleash heavenly wrath on her.

“I don’t want to fight you,” said Morgan, impressed with the ferocity she was able to summon behind her words. “That book I want is very powerful. If you bring it to me, I’ll show you.” The two men glanced at each other. Aziraphale nodded cautiously, and darted to a shelf on the far wall. Crowley glared at her. Aziraphale returned moments later grasping _Death Of Destiny_ like he feared it would crumble between his fingers. Morgan could feel her heart pounding. A door to the Library could be manifested by a trained Librarian anywhere with a large quantity of books. Once she had secured _Death Of Destiny_ , what better place to summon it than this abundant bookshop?

“If I hand this to you,” said Aziraphale slowly, “can we trust that your demonstration does not involve inflicting harm on us?” 

“Yes,” she said. “All I want is the book.” Aziraphale cautiously held the book out to her, and she took it. He retreated back to where Crowley was standing. She thumbed through the pages, making sure this was the real thing and not counterfeited. 

“Well?” Said Crowley indignantly. Morgan agreed— no point in waiting any longer. She set her eyes on the bookshop door.

‘“ **Open to the Library,’** ” she said, giving the word Library its full value in the Language, and felt the tattoo scrawled across her back shift and writhe as the link was established. She felt a dizzying rush in her mind like she had jumped headfirst into water, and she knew the two men felt it too. She seized on their disorientation and launched into a sprint across the shop, ducking between them before they snapped to their senses. She reached the door and twisted the knob, throwing the door open and stepping through. Aziraphale and Crowley had begun shouting but their voices faded as Morgan left the shop, and alternate B-617, for good.

The door closed behind her and Morgan found herself in the colossal halls of the Library. She had no fear of being followed, as the shop door had re-established itself as part of the world she’d left behind, and she let out a sigh of relief knowing that she and the book were safe. A glance to her right showed her that she was in the _North American Gothic 1600-1900_ section, roughly 20 minutes away by foot from her superior’s office. She made a mental note to drop by the Library’s research office and correct their intel. It still confused her greatly— _an angel and a demon working together in a London bookshop._ She chuckled to herself. _How strange._

**Notes for the Chapter:**

> GLOSSARY--
> 
> The Library: An all-seeing, inter-dimensional library whose mission is to collect and preserve books from all alternate universes.
> 
> The Language: The otherworldly language which Librarians use for their magic, can be used for warping reality to do whatever the speaker wants it to do, within limits. When heard by someone not bound to the Library, the spell sounds like the listener's native language.
> 
> Runes: The tattoos a Librarian has on their spine that binds them to the Library and channels their magic use.


	4. Epilogue

The next time Crowley knocked on the door to Aziraphale’s shop, it was past midnight. Seven hours had passed since the mysterious girl had vanished. Aziraphale opened the door and Crowley strode past him. 

“I’ve examined every book in the shop and not a single one is damaged. No traces of her or her magic,” said Aziraphale.

“ Well I’ve just been around the whole world and she’s nowhere to be seen,” said Crowley incredulously, flopping down onto Aziraphale’s couch. “Hell, I even went to some other worlds. Not even on bloody Alpha Centurai,” he whined. Aziraphale sat in an armchair while Crowley sprawled his limbs over the couch. 

“She’s not one of ours,” said Aziraphale.

“Definitely not one of ours either.”

“Should we report her to someone?”

“To whom?” Crowley put on a mocking tone. “Hi Gabriel. Sorry to bother you. A human girl showed up, spoke Enochian, rattled my bookshop, and then _fucking disappeared_. He’d think you were mad!” Aziraphale shifted in his seat.

“I suppose you’re right.”

“And my lot— if they were to even get a whiff of this— I’d be a puddle of holy water before you could say ‘ _diablo fou’._ Not to mention that they would know I was associating with the enemy.” Wearily, Crowley put his hands on his face and groaned into them. 

“So, what now?” Said Aziraphale. Crowley raised an arm lazily.

“I think our best plan is to get hopelessly drunk and pray that she never comes back.”

And she never did. 


End file.
